Endnote 1

n = Number of time steps in a day (96)
i = Current time step
staffing = Calculated staffing requirements
stepsHr = Time steps in one hour (4)
paidHrs = Paid Hours in a Day as specified in staffing forecast
pOverhead = Planned Overhead percentage as specified in staffing forecast

Endnote 2

The Total/Average value of Service Level in the Contact Center Performance report is calculated as a weighted average, where for the weight coefficient we use the TotalNumberCallsDistributed configuration option.

That is, for an Activity when we define the Quality of Service Statistic type in the WFM Web, we are required to specify three statistics:

Service Factor

Distributed Interactions

Average Speed of Answer

(plus two time ranges required for Service Factor statistic calculation)

The Number of Distributed Interactions statistic (or TotalNumberCallsDistributed) plays the role of the weight coefficient in order to calculate the weighted average value of Service Level per:

Timestep

If we calculate Service Level for the same activity several objects (for example, across some Queues) this gives us the possibility to get an accurate result rather then a simple average.

Day

A weighted average gives a very accurate result in comparison with simple average.

So the calculation of Total Service Level per day is done by the formula:

This example shows that a timestep with Service Level=90 where only one call has been processed should have minimal impact on the overall Service Level for the day, in comparison with a timestep where SL=20 and 150 calls have been processed. This is the reason the calculation is done in this way.

The user won’t be able to see TotalNumberCallsDistributed in the report, as this value is stored in the WFM database for internal purposes only (in the table WM_perf_activities in the field WM_distrib_calls, for each activity and for each timestep).

Also keep in mind that TotalNumberCallsDistributed is not the same as Interaction Volume, since in general Interaction Volume is configured as TotalNumberCallsEntered (Answered + Abandoned), while TotalNumberCallsDistributed is the number of calls which are being distributed from the queue.